Energy at the Surface of the Earth

Energy at the Surface of the Earth: An Introduction to the Energetics of Ecosystems presents way of looking at the manner in which the biological, physical, and cultural systems that mantle the landmasses of our planet receive, transform, and give off energy, which is an essential condition of existence that takes many forms. Energy conversions establish the climate in which these systems operate.
The principal forms of energy that are converted at the ecosystem scale include radiant, latent, mechanical, chemical and fossil, and thermal. The book begins with radiant energy absorbed by ecosystems—a phenomenon that is independent of their surface temperature and that can be looked on as a burden or a gift, depending on circumstances. An increase in such absorption raises surface temperature, as described in the fulcrum chapter of the book, Chapter VIII. This increase in turn sets into action outflows of energy that by the first law of thermodynamics are equal in energy units, although not necessarily equal in quality to the inflows. The final chapters deal with vertical stratification and areal contrasts in energy budgets, the augmented energy budget of the city, and the responses that serve to keep the budget balanced.

Preface

Acknowledgments

Chapter I Introduction

The Energy Budget

The Locus of Energy Transformation

Energy in Ecosystems

References

Chapter II Surface Characteristics of Ecosystems

Ecosystem Size and Structure

Factors in Coupling of an Ecosystem with the Sun

Radiative Coupling with the Atmosphere

Coupling of an Ecosystem with the Atmosphere by Turbulence

Coupling with the Substrate

Ecosystems at the Active Surface of the Earth

References

Chapter III Direct Solar Radiation

Nature and Significance of the Solar Beam

Geometry of the Solar Beam

Incidence of the Solar Beam on Ecosystems under the Changeable Atmosphere

Incidence of the Solar Beam on Ecosystems of Different Attitudes

Spatial Patterns and Ecological Consequences

References

Chapter IV Diffuse Solar Radiation

The Diffuse Flux Generated by Rayleigh Scattering

Diffuse Radiation under a Hazy Atmosphere

Diffuse Radiation under a Cloudy Atmosphere

Spectral Composition of the Diffuse Flux

Variations over Time

Spatial Variation

References

Chapter V Total Incoming Solar Radiation

The Relative Contributions of the Component Fluxes

Flux Densities of Total Solar Radiation Incident on Ecosystems

Spectral Composition of the Incident Solar Flux

Determining the Combined Solar Fluxes on Horizontal Surfaces

Variations in Total Solar Radiation over Time

Spatial Differences in Total Solar Radiation

References

Chapter VI Incoming Longwave Radiation

Magnitude and Significance of the Flux

Radiation under a Cloudless Sky

Sources of Variation under Clouds

Measurement and Estimation

Variations over Time

Spatial Variations in Incoming Longwave Radiation

References

Chapter VII Radiant Energy Absorbed by Ecosystems

Ecosystem Characteristics That Affect Absorption of Radiant Energy

Geometric Components of Radiant Energy

Spectral Composition of Radiant Energy Absorbed by Ecosystems

Spectral Patterns of Absorptivity Coefficient

Variations in Radiant-Energy Intake over Time

Spatial Patterns of Absorbed Radiant Energy

The Temperature-Independent Intake of Energy

References

Chapter VIII Surface Temperature of Ecosystems

Defining Surface Temperature T0

Significance of Surface Temperature

Determining Surface Temperature

Variations over Time

Spatial Patterns

References

Chapter IX Longwave Radiation Emitted by Ecosystems

The Longwave Flux

Role in Ecosystem Energy Budgets

Determination of Upward Longwave Radiation

Variations in the Upward Flux of Longwave Radiation

References

Chapter X Resultants of the Upward and Downward Radiation Fluxes

The Net Exchange of Longwave Radiation between Ecosystem and Atmosphere

Factors in the Net Exchange of Energy by Longwave Radiation

Combining All the Radiation Fluxes: The Net All-Wave Deficit or Surplus

Variations in Net All-Wave Radiation over Time

Spatial Contrasts in Net All-Wave Radiation

References

Chapter XI Fixing of Carbon by Ecosystems

Gross Primary Production

Net Primary Production

Influences on Productivity and Translocation

References

Chapter XII The Release of Carbon Fixed in Ecosystems

Biological Energy Conversions

Ecosystems in Steady State

Energy Conversion by Fire

References

Chapter XIII Broad-Scale Transformations of Fossil Energy

Fossil Energy in the Management of Extensively Exploited Ecosystems

Fossil-Energy Conversions in Farm Operations

Fossil Energy in Ecosystems and Mosaics

Energy in Circulation Systems

References

Chapter XIV Phase Changes of Water in Ecosystems: I. Freezing and Thawing

Presence and Characteristics of Snow Cover in Ecosystems

The Energy Budget of Melting Snow Cover

Effects of Terrain and Weather on the Energy Budget

Thawing of Soil and Ice

Freezing

References

Chapter XV Phase Changes of Water in Ecosystems: II. Vaporization

Energy Conversion by Vaporization

Ecosystem Characteristics

Atmospheric Removal of Vapor from Ecosystems

Variations in Latent-Heat Conversions

References

Chapter XVI The Flux of Sensible Heat from Ecosystems

Ecosystem Characteristics

The Atmospheric Environment as a Sink or Source for Sensible Heat

Ecosystem-Atmosphere Relationships

Variations in the Removal of Sensible Heat from an Ecosystem

Spatial Contrasts

References

Chapter XVII Substrate Heat Flux in Terrestrial Ecosystems

Role of the Soil in the Ecosystem

Thermal Diffusivity and Admittance

Heat Storage in the Daily Cycle

Aperiodic Variations

Heat Storage in the Annual Cycle

Spatial Patterns of Soil-Heat Flux

References

Chapter XVIII Substrate Energy Storage in Aquatic Ecosystems and Its Place in Their Energy Budgets

Ecosystem Structure

Coupling with the Sun

Coupling with the Atmosphere

Advection of Upstream Heat or Cold in Ecosystem Energy Budgets

Variations in the Energy Budget

References

Chapter XIX Potential and Kinetic Energy in Ecosystems

Potential Energy in Ecosystems

Potential Energy in Ecosystem Environments

Kinetic Energy of Water in Ecosystems

Atmospheric Kinetic Energy in Ecosystems

Variations of Potential and Kinetic Energy

References

Chapter XX Energy Budgets at Different Depths in Ecosystems

The Ecosystem as Environment of Its Members

Radiant-Energy Absorption at Different Levels

Ventilation

Vertical Profiles

Substrate Energy

Stratification of Energy Budgets

References

Chapter XXI Ecosystem Contrasts

The Origins of Contrast

Contrasts in Temperature-Independent Fluxes

Contrasts in Surface Temperature

Contrasts in Emitted Radiation and Energy Conversion

Contrasts in Ecosystem Couplings

Contrasts in the Outputs from Ecosystems

Time Variations in Contrast

The Variegated Mantle of the Earth

References

Chapter XXII Energy Conversions at Nodes

Points of Energy Concentration

Characteristics of the Urban Interface

Modified Radiant-Energy Intake

Fossil-Energy Augmentation

Temperature-Dependent Energy Fluxes

Responses of Urban Ecosystems

References

Chapter XXIII Integrating the Energy Fluxes

Models of Ecosystem Energy Budgets

Effects of Changes in Radiant-Energy Intake

Effects of Changes in Surface Characteristics

Effects of Changes in Atmospheric Conditions

The Structure of Ecosystem Energy Budgets

Conclusion

References

Index